一刀[ittou] sword
一刀彫り[ittoubori] one-knife carving
一刀両断[ittouryoudan] cutting in two with a single stroke
印刀[intou] seal-engraving knife
円刃刀[enjintou] round-edged scalpel

快刀[kaitou] (literary) sharp sword
快刀乱麻[kaitouranma] solving a problem swiftly and skillfully
懐刀[futokorogatana] confidant
儀刀[gitou] ceremonial sword
軍刀[guntou] saber

妖怪[youkai] ghost
妖術[youjutsu] black magic
妖術者[youjutsusha] magician
妖精[yousei] fairy
妖魔[youma] ghost

妖しい[ayashii] suspicious
妖艶[youen] fascinating
面妖[menyou] weird
妖女[youjo] enchantress
妖気[youki] ghostly